Expeditious Pechmann Condensation by Using Biodegradable Cellulose Sulfuric Acid as a Solid Acid Catalyst

Abstract

A facile synthesis of coumarins was performed in excellent yields via Pechmann condensation by using different type of phenols and ethylacetoacetates under solvent–free media using both conventional method and microwave irradiation in short reaction times is described. The reaction workup is very simple, and the catalyst can be easily separated from the reaction mixture and reused several times in subsequent reactions.

Keywords:

• Cellulose sulfuric acid
• coumarins
• Pechmann condensation
• solvent-free conditions

ACKNOWLEDGMENT

Financial assistance from the council of Scientific and Industrial Research (Grant No. 01(2061)/06/EMR-II), New Delhi, is greatly acknowledged.

Notes

^a Yields refer to the pure isolated recovered catalyst.

Note. Reaction conditions: Phenol 1 (1 mmol), β-ketoester 2 (1 mmol), and cellulose sulfuric acid (0.1 g) were stirred at room temperature.

^a Yields refer to the pure isolated recovered catalyst.